TY - JOUR
T1 - Repeatability of vessel density measurements of optical coherence tomography angiography in normal and glaucoma eyes
AU - Venugopal, Jayasree P.
AU - Rao, Harsha L.
AU - Weinreb, Robert N.
AU - Pradhan, Zia S.
AU - Dasari, Srilakshmi
AU - Riyazuddin, Mohammed
AU - Puttiah, Narenda K.
AU - Rao, Dhanraj A. S.
AU - Devi, Sathi
AU - Mansouri, Kaweh
AU - Webers, Carroll A. B.
PY - 2018/3/1
Y1 - 2018/3/1
N2 - Aims To compare the intrasession repeatability of peripapillary and macular vessel density measurements of optical coherence tomography angiography (OCTA) in normal and glaucoma eyes, and to evaluate the effect of signal strength of OCTA scans on the repeatability. Methods In a cross-sectional study, three optic nerve head scans each of 65 eyes (30 normal, 35 glaucoma eyes) and three macular scans each of 69 eyes (35 normal, 34 glaucoma eyes) acquired in the same session with OCTA were analysed. Repeatability was assessed using within-subject coefficient of repeatability (CRw) and variation (CVw). Effect of signal strength index (SSI) on repeatability was evaluated with repeated-measures mixed-effects models. Results CRw (%) and CVw (%) of peripapillary measurements in normal eyes ranged between 3.3 and 7.0, and 2.5 and 4.4 respectively, and that in glaucoma eyes between 3.5 and 7.1, and 2.6 and 6.6. For the macular, these measurements ranged between 4.1 and 6.0, and 3.3 and 4.7 in normal eyes and 4.3 and 6.9, and 3.7 and 5.6 in glaucoma eyes. Repeatability estimates of most measurements were similar in normal and glaucoma eyes. Vessel densities of both peripapillary and macular regions significantly increased with increase in SSI of repeat scans (coefficients ranging from 0.15 to 0.38, p<0.01 for all associations). Conclusions Repeatability estimates of OCTA measured peripapillary and macular vessel densities were similar in normal eyes and eyes with glaucoma. SSI values of the scans had a significant effect on the repeatability of OCTA with the vessel density values increasing in scans with higher SSI values.
AB - Aims To compare the intrasession repeatability of peripapillary and macular vessel density measurements of optical coherence tomography angiography (OCTA) in normal and glaucoma eyes, and to evaluate the effect of signal strength of OCTA scans on the repeatability. Methods In a cross-sectional study, three optic nerve head scans each of 65 eyes (30 normal, 35 glaucoma eyes) and three macular scans each of 69 eyes (35 normal, 34 glaucoma eyes) acquired in the same session with OCTA were analysed. Repeatability was assessed using within-subject coefficient of repeatability (CRw) and variation (CVw). Effect of signal strength index (SSI) on repeatability was evaluated with repeated-measures mixed-effects models. Results CRw (%) and CVw (%) of peripapillary measurements in normal eyes ranged between 3.3 and 7.0, and 2.5 and 4.4 respectively, and that in glaucoma eyes between 3.5 and 7.1, and 2.6 and 6.6. For the macular, these measurements ranged between 4.1 and 6.0, and 3.3 and 4.7 in normal eyes and 4.3 and 6.9, and 3.7 and 5.6 in glaucoma eyes. Repeatability estimates of most measurements were similar in normal and glaucoma eyes. Vessel densities of both peripapillary and macular regions significantly increased with increase in SSI of repeat scans (coefficients ranging from 0.15 to 0.38, p<0.01 for all associations). Conclusions Repeatability estimates of OCTA measured peripapillary and macular vessel densities were similar in normal eyes and eyes with glaucoma. SSI values of the scans had a significant effect on the repeatability of OCTA with the vessel density values increasing in scans with higher SSI values.
KW - optical coherence tomography angiography
KW - intra-session repeatability
KW - peripapillary vessel density
KW - macular vessel density
KW - signal strength index
KW - OPEN-ANGLE GLAUCOMA
KW - DIABETIC-RETINOPATHY
KW - MACULAR DEGENERATION
KW - DISC PERFUSION
KW - VISUAL-FIELD
KW - NEOVASCULARIZATION
KW - DEFECTS
U2 - 10.1136/bjophthalmol-2017-310637
DO - 10.1136/bjophthalmol-2017-310637
M3 - Article
SN - 0007-1161
VL - 102
SP - 352
EP - 357
JO - British Journal of Ophthalmology
JF - British Journal of Ophthalmology
IS - 3
ER -